1. Field of the Invention
The present invention relates to a protective circuit module and a secondary battery having the same.
2. Description of the Related Art
A lithium ion secondary battery is generally composed of a positive electrode plate, a negative electrode plate, an electrolyte and a separator, and is capable of repeated use after recharging the battery.
Lithium ion secondary batteries typically include a protective circuit module (PCM) for protecting the battery against excessive charging/discharging or overcurrent. The protective circuit module may include a variety of conductive metal patterns including a protective circuit on a substrate.
The protective circuit module can be connected through a conductive tab (lead plate) to a bare cell including an electrode assembly. In order to secure a space for welding of a positive electrode tab to a cap plate of the bare cell, a portion of the substrate may be cut by a certain length and removed. Further, a side of the substrate where a dummy tab is positioned to balance with the positive electrode tab may also be cut by a certain length and removed.
As a result, the substrate may lack surface area for the installation of devices such as a protective circuit and conductive metal pattern thereon, since a given portion of the substrate was truncated as described above. Further, even though individual devices may be installed on the substrate, the spacing (distance) between the devices may be less than desirable, which may result in high susceptibility to a short circuit even under weak impact.